Effect of Slash‐and‐Burn Shifting Cultivation on Rainforest Birds in Mizoram, Northeast India

Abstract

Abstract: Slash‐and‐burn shifting cultivation, or jhum, the predominant form of agriculture in the hill tracts of northeast India, is believed to have caused considerable loss of forest cover in the species‐rich tropical rainforests of the region. In this study I sought to understand how rainforest bird communities are affected by shifting cultivation in Mizoram State. I studied bird occurrence and abundance patterns in secondary successional and mature tropical rainforests in a shifting‐cultivation habitat mosaic in Dampa Tiger Reserve. To compare replicate sites in fallows aged 1, 5, 10, 25, and 100 years with undisturbed primary forest, I used systematic strip‐transect sampling over the winter and early summer ( breeding) seasons during 1994–1995. Many forest bird species, especially those with ranges restricted to northeast India, declined in abundance or disappeared in successional fallows that had regenerated for ≤10 years. Birds that colonized or increased in abundance in regrowth habitats were mainly common and widespread species of open‐country and secondary‐forest habitats, and of low importance for conservation. Primary forest was the main habitat for specialized forest birds, intrinsically rare species, and elevational migrants. Although protection and conservation of relatively undisturbed mature forests is imperative in the core area of the reserve, management in the buffer zone for long‐rotation shifting cultivation (>10‐year cycles) instead of plantation of monocultures may be important until alternate means of livelihood are available to cultivators.